Adjust a clip's source in and out points without moving it on the timeline. Apply positive or negative offsets to shift source content while preserving clip position.
Slip a clip (change its source in/out without moving it on the timeline)
| Name | Required | Description | Default |
|---|---|---|---|
| clipIndex | Yes | Clip index | |
| trackType | Yes | Track type | |
| trackIndex | Yes | Track index | |
| offsetSeconds | Yes | Offset in seconds (positive = slip forward, negative = slip backward) |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden. It discloses the key behavior that the clip's timeline position stays fixed while its source in/out changes, but it does not mention permissions, linked-clip effects, reversibility, or what happens on failure.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single front-loaded sentence with no wasted words. It defines the operation and its key constraint immediately.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
The definition is adequate for a simple clip-editing operation with fully documented parameters, but because there are no annotations and no output schema, it could do more to disclose prerequisites or side effects. The agent knows what the tool does, but not all conditions needed to call it confidently.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so the input schema already documents all four parameters, including the positive/negative convention for offsetSeconds. The description adds no parameter-specific meaning beyond the schema, which is acceptable at the baseline for fully documented schemas.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description states a specific editing verb and resource ('Slip a clip') and clarifies the core effect: changing source in/out without moving the clip on the timeline. It is clearly different from a generic move or trim, though it does not explicitly contrast with the sibling slide_clip tool.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
There is no explicit guidance on when to use this tool versus alternatives such as slide_clip, set_clip_in_out, or move_clip_to_track. The parenthetical implies the operation's purpose but does not tell the agent when this is the correct choice.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.